1. Field of the Invention
This invention relates generally to a mulching arrangement, and, in particular, to a mulch plate attachment for lawn mowers which recirculates grass clippings under the lawn mower until fine particles of mulch are deposited onto the lawn.
2. Description of the Prior Art
Mulching is a process for maintaining an even soil temperature, controlling weeds, and enriching soil, whereby a mixture of organic material, such as straw, peat moss, or leaves are spread over a landscape. When grass clippings from a lawnmower are sufficiently reduced in size to small particles, they may serve as a mulching agent. Conventional mowers, however, are incapable of refining grass clippings to that desired state. The typical lawnmower propels a rotary blade to cut grass into clippings and either deposits those clippings onto the lawn or directs them into a catcher. Clippings discarded on lawn take weeks to decompose and can smother the soil rather than fertilize it, unless raked and removed. Catchers are undesirable in that mowing must be frequently interrupted to empty the contents. In either event, time is lost which could be spent cutting additional grass.
Alternatively, mulching lawnmowers can reduce expenses, increase crew efficiency, and decrease waste. Mulching lawnmowers are designed to cut grass clippings into tiny particles that decompose quickly once returned to the lawn, providing nourishment and moisture to the underlying soil. In theory, mowing time can be cut, fertilizer, trash bag, and water expenses can be reduced, and productivity can be enhanced. Unfortunately, mulching lawnmowers used today are only useful under special conditions and require constant maintenance. For example, mulching mowers normally require short, dry grass, flat landscapes, and frequently honed blades. These mowers also leave uncut strips that necessitate recutting, especially on lawns having a high moisture content, tall grass, or hills. In addition, moist grass that is cut has a tendency to stick to the underside of the conventional mulching mower, reducing the mulching capability and eventually dropping clumps of grass on the lawn.
A variety of mulching mowers are available in the prior art which have either realized the foregoing shortcomings or have been too complex to operate reliably. For example, U.S. Pat. No. 5,117,616 issued to McLane introduces a mulching lawnmower that deposits clippings in front of the mower for recirculation. The McLane mower comprises a deck which covers a rotating blade and a curved deflector which lies adjacent an opening provided in the deck between the front wheels. The deflector redirects air and grass exiting the opening downward in front of the mower. The positioning of the opening and deflector at the front of the deck allows the mower to run over grass clippings a second time, but if the grass is too wet, the opening clogs and suction under the deck becomes insufficient to lift the wet clippings off the lawn and into the cutting area. An air-floated mulch recycle system, issued to Fassauer in U.S. Pat. No. 5,123,235, employs an air-floated housing having a rotatable cutting blade, an open bottom, an air intake opening conduit and a rear discharge port. A mulch recycling system comprised of a conduit attaches to the discharge port to receive grass clippings produced by the mower for delivery to the front of the mower for recutting. An air impeller means pressurizes air to float the mower, but inhibits the mower's ability to draw grass clippings into the mulch recycling system. Moreover, dry grass is preferred for cutting, whereas wet clippings are difficult to lift into the blade, stick to the underside of the housing, and clog the tubular chute used in the mulching system. Another mulching device is found in U.S. Pat. No. 5,048,279 issued to Badawey, and is utilized as a leaf mulcher for use with a rotary blade lawnmower. The leaf mulcher comprises a rotary blade lawnmower, a grass outlet and a screen mounted on the mower over the outlet. The screen provides a cutting edge for leaves dispersed from the outlet of the mower but does not facilitate the mulching of grass clippings, is easily clogged, and is ineffective on damp lawns.
While the aforementioned devices disclose various designs for mulching debris emitted from a rotary lawnmower, no such device teaches the benefits of a low profile design that is adaptable to most mowers and capable of reducing clippings of various types, and under diversified conditions, to a mulch for discarding as a nutrient into lawns. Therefore, there exists a need for a mulching lawnmower that is able to reduce clippings from tall and wet lawns into fine particles for depositing back into the lawns as a fertilizing nutrient. This invention is intended to address and solve these problems which are not adequately resolved by the prior inventions.